Carbon rovings as strain sensors for structural health monitoring of engineering materials and structures

Abstract

A prospective method for structural health monitoring of engineering materials and structures is based on embedded strain sensors in the form of electrically conductive carbon rovings. This article presents the results of the application of carbon rovings and the development of flexible textile fabrics based on these rovings for measuring the deformation in engineering materials, including concrete and polymer-and cement-based composites. The possibility of using carbon rovings as a strain sensor is demonstrated via measurements in tensile and four-point bending tests. The experimental setups and methods for measuring the electrical resistance of carbon roving as a function of strain in the roving, concrete, and composites are described. A good correlation has been found between the electrical resistance-strain curve of the carbon roving (used as a calibration curve) and the measurements in the concrete and polymer composites from tensile tests. The difference in the character of the flexural behavior and the electrical signal in the carbon roving cement-based composite, affected by the stitch type and shape of the carbon roving cross section in textile fabric, was found through four-point bending tests.

Experimental and numerical analysis of strain gradient in tensile concrete prisms reinforced with multiple bars

“…However, a scientific methodology to rectify the deficiency has been in lack. A number of techniques have been developed for the strain monitoring of RC specimens [10,11]. The most straightforward and commonly used method is measuring the displacement between two points to obtain average strain in the gauge length.…”

Detecting Damaged Zones Along Smart Selfsensory Carbon Based TRC by TDR

“…Since the carbon rovings are electrically conductive, they can be used both as the main reinforcement system and as the sensory agent [1,4,5,13,16,17]. The potential of using carbon rovings as an integrated sensory agent has been presented in the literature for various sensory purposes such as: detecting cracking [7], estimating strain [7,13,16,17], monitoring the mechanical loading [1,4,5], identifying infiltration of water through cracked zones [6,12], etc. The commonly used approaches for the electrical measurement are based on direct current (DC) electrical circuits by two-probes monitoring setup [13], four-probes monitoring setup [16], Wheatstone bridge configurations [7,17], or by alternating current (AC) electrical circuits [4,5].…”

Monitoring capabilities of various smart self sensory carbon-based textiles to detect water infiltration

“…The high tensile strength of the rovings and their high resistance against corrosion enable the production of thin-walled and structurally strong TRC elements. The use of electrically conductive rovings, such as carbon rovings, that are characterized by high mechanical performance enables the rovings to serve both as the main reinforcement system as well as the sensory agent for detecting mechanical loading (Christner et al, 2012; Goldfeld et al, 2016a, 2017b; Wen and Chung, 1999; Wen et al, 2000), strain (Horoschenkoff and Christner, 2012; Quadflieg et al, 2016; Teomete, 2015), cracking (Goldfeld et al, 2017a; Goldfeld and Yosef, 2019); or water infiltration (Goldfeld and Perry, 2018, 2019; Goldfeld et al, 2016b, 2016c).…”